The present invention relates to a system for the remote control, maintenance or fluid injection for a submerged satellite well head, particularly a submerged head for a satellite producing oil well or for a satellite well used for stimulating the oil-field.
At present it is standard procedure to remotely control submerged satellite well heads from a central production storage station or platform. Remote control lines are then used which convey the necessary electrical or hydraulic energy from the central platform to the sea bed and then to the satellite well heads on the sea bed. When intervention is necessary on the well head to carry out measurements or maintenance a boat equipped with the necessary equipment is used.
The difficulties involved in conveying remote control energy over relatively large distances on the sea bed, the impossibility of rapidly being able to directly work on the well heads and the relatively high cost of using special boats for this work constitute serious disadvantages.
To obviate these disadvantages, French Pat. No. 1 506 300 and its Addition 2 165 811 propose the use of a system of the type having a platform fitted with equipment usable for the remote control and maintenance of the well head and located substantially perpendicular to said well head, by means of a pipe connecting the platform to the well head, a control device located on the well head or in the immediate vicinity thereof and at least one remote control line connecting the platform to the remote control device.
In this known system the platform is submerged at a limited depth, so that it is not subject to the action of swell, waves and surface currents. Work can only be carried out on the well from the platform after fitting at least one energy transmission line between platform and surface boat.
Therefore this system requires on the one hand the provision on the platform of equipment which, without any danger of damage or deterioration, can withstand permanent immersion and on the other the presence of divers for any intervention.
It is also well known to stimulate an oil-field by permanently or intermittently injecting fluids such as water or chemical products through auxiliary or satellite wells. The fluids are fed to the stimulating satellite wells through submarine ducts, the fluid source and the energy delivering means necessary for the injection process being located on a central production platform.
This known system necessitates the installation and maintenance of a large network of expensive ducts. Due to the length of the ducts, the energy delivering means, in particular the pumps, must be dimensioned in order to overcome the load losses along the ducts.